My setup is similar to the issue posted here:
I am running Shiny Server using R 3.5.1 on CentOS 7.5. Furthermore, the same thing happens when I try to run RMarkdown with Shiny from RStudio Server 1.2 Preview.
The page loads, but the static ggplot2 image generated by the RMarkdown file shows up as a broken link in the page.
The log file shows the following warnings:
Warning in file.rename(from, to) : cannot rename file '/tmp/shinytidy/rmarkdown/ffd833b364179a334684ed3d731da33e/rmd_ffd833b364179a334684ed3d731da33e_files/figure-html' to '/tmp/shinytidy/rmarkdown/ffd833b364179a334684ed3d731da33e//tmp/shinytidy/rmarkdown/ffd833b364179a334684ed3d731da33e/rmd_ffd833b364179a334684ed3d731da33e_files/figure-html', reason 'No such file or directory'
I have found that changing output from
html_document causes the image to properly render.